GunDoc,
Damned if I know, because I've never messed all that much with either version of the 6.8 SPC, mostly because it never seemed like a real solution to any hunting "problem" I've encountered--and I'm primarily a hunter.
But that's what I hear and read from people who have, and I know some SPC experts. But from other experience, suspect the twist is FAR behind the throat dimensions.
As mentioned earlier, do know that Bill Wilson (who I hunted with using his 6.8 AR's almost a decade ago) decided to develop another round that he's pretty sure works better for general big game hunting in an AR-15, the .300 HAM'R. He's pretty sure because of shooting hundreds of pigs, and other animals, with it.
